1. Field of the Invention
The invention relates to a system for the analysis and comparison of surfaces of fired bullets. The invention also relates to a method of analyzing and comparing the surfaces of fired bullets using the inventive system.
2. Description of Prior Art
Forensic firearm examiners have to match bullets in order to determine if they have been fired from the same gun. Under present procedures, two bullets are placed under a comparison microscope, and the bullets are viewed at the same time by the examiner who compares the characteristics of their outer surfaces to determine if there is a match between them. As the reason for determining whether there is or is not a match is to present evidence in legal proceedings, the final step in the determination is normally performed by a human being who can subsequently appear as a witness in the legal proceeding. Nevertheless, the burden of the examiner could be greatly alleviated by an automated system for providing degree of match between pairs of bullets. Such system would preferably be an optoelectronic system.
Optoelectronic systems for comparing bullets are known in the prior art as at, for example, U.S. Pat. No. 3,680,966, Cofek et al, Aug. 1, 1972. However, the Cofek et al apparatus examines the flash hole of cartridge cases after manufacture but before firing.
U.S. Pat. No. 3,780,614, Maier, Dec. 25, 1973, teaches a multiple bullet and cartridge holder for forensic microscopes which provide improved indexing and manipulation.
The problem is also addressed in COMPUTER IDENTIFICATION AND CLASSIFICATION OF BULLETS, a Dissertation Submitted in Partial Fulfillment of the Requirement for the Degree of Doctor of Philosophy (Electrical Engineering) at the Polytechnic Institute of New York by Geoffrey Y. Gardner, June 1976.